LV cables are now paper-insulated, rather than uninsulated (which made
no sense). MV cables are rubber-insulated as before. HV cables are now
plastic-insulated (which they already visually appeared to be). MV and
HV cables are still crafted by adding insulation onto lower-tier cable,
rather than by insulating raw copper; this matches the way machines are
upgraded between tiers rather than crafted afresh.